Method of mixing fluids



9.45. c. s. GERHOLD METHOD OF MIXING FLUIDS 2 Sheets-Sheefi Filed April 21, 1943 .7g z forzze Jrz/erz for"; ("Zarerzze GI Gerfiald Aug. 14, 1945. c. s. GERHOLD 2,332,371- METHODIOF MIXING FLUIDS V Filed April 21, 1943 2 Sheets-Sheet 2' CZQrezzce Gerkold Patented Aug. 14, 1945 METHOD OF MIXING FLUIDS Clarence G. Gerhold, Chicago, 'Ill., assignor to Universal Oil Products Company, Chicago. 111., a corporation of Delaware Application April 21, 1943, Serial No. 483,919

9 Claims.

This invention relates to an improved method of mixing fluids and more particularly to a method of obtaining an intimate mixture of two or more immiscible phases.-

The successful application of a number of processes depends upon obtaining an intimate mixture of two or more immiscible phases with a minimum power requirement.

This invention offers a method by which very intimate mixing may be obtained between two or more fluids by carrying out the mixing operation under varying pressure conditions. The pressure on the material undergoing treatment is alternated between one at which the material is completely liquid and one at which it is partially vaporized. During the operation it is preferable that the material being mixed is maintained in a turbulent state sufllcient to prevent vapor separation.

By'alternately decreasing and increasing the pressure on the material being mixed to an amount sufllcient to cause alternate vaporization and condensation, a large number of. points of stress will be set up uniformly distributed throughout the material and will result in a much more uniform and complete degree of mixing or emulsiflcation than is obtained by conventional methods.

Broadly this invention is concerned with a method of mixing fluids which comprises alternately decreasing and increasing the pressure on said fluids to cause alternate vaporization and condensation of at least a portion thereof while maintaining the mixture in a state of turbulence I sufflcient to prevent substantial vapor separation.

In a more specific embodiment, the present invention comprises a method of emulsifying immiscible liquids which comprises alternately decreasing and increasing the pressure -on said liquids to cause their alternate partial vaporization and substantially complete condensation while maintaining the liquids in a-state of turbulence sufilclent to prevent vapor separation.

This invention may be advantageously applied to the mixing of fluids in general and in particular to processes requiring intimate mixing of two or more immiscible phases for their successful operation. As examples of processes to which this invention may be applied may be mentioned the alkylation of parafllns with olefins using hydrogen fluoride or sulphuric acid.

In order to more clearly describe the invention, reference is made to the accompanying diagrammatic drawings and the following description thereof.

Figures 1, 3, 4, 5 and 6 of the drawings illustrate several types of apparatus in which this invention may be successfully carried out. Fig- 'ure 2 of the drawings is an enlarged detail of a portion of the apparatus shownin Figure 1.

Referring now to Figures 1 and 2: 1 Materials to be mived are introduced to the system through line I controlled by valve 2. It is,

of course, within the broad scope of the invention to introduce the various materials into the system through separate lines but these have been eliminated in order to simplify the drawings. Materials to be mixed are directed by line 3 to heat exchanger 4 through which they will pass thereby attaining the desired temperature. exchanger 4 the mixing materials will be directed by means of line 5 into a series of vertical U- bends 6. U-bends 6 are graduated in length in order to compensate for line pressure drop through the system.

In order to maintain the desired temperature in heat exchanger 4, suitable convective fluid is introduced thereto by means of line 1 controlled by valve 8 and removed therefrom by means of line 9. Valve 8 is a conventional type of diaphragm operated valve which is interconnected by means of line to to controller II. Control instrument I l is in turn connected by means 01' a capillary tube or electrical conduit l2 to a tem- After passing through the series of vertical U- bends 8, material will be discharged into float chamber 15 containing float l6 which is connected by a series of links and lever arm H to valve 18. The combination of the float in chamber l5 and regulating valve I8 is arranged to .on rising material to cause vaporization when it reaches the upper end of each U-bend. As the material passes in a downward direction, the hydrostatic pressure will increase and cause condensation. Therefore, as the material succes- From heat sively'rises and falls in U-bends 5, it will be subject to alternate changes in pressure which in turn will effect alternate vaporization and condensation.

desired degree by means or a suitable heat convective material supplied through line 80 and controlled by valve 8|. The heat exchange medium may be withdrawn from exchanger by The material leaving chamber passes 5 means of line 82. By continually circulating the.

' through line I9 to pump 20 wherefrom it is directed through line 3 to again pass through the system. Mixed material is removed from the system by means of line 2| controlled by valve 22.

material to be mixed through the system and alternately changing the pressure therein by means of regulator 69 and pump 55, alternate vaporization and condensation will take place thereby The rate of charge to the system, of course, ill 10 effecting very intimate mixing. Mixed materials be substantially equivalent to the rate oi withdrawal of mixed materials.

In Figure 3 is illustrated another form of apparatus in which the invention may be conducted.

may be withdrawn from the system through line 83 controlled by valve l4.

. In Figure 5 another form of apparatus suitable for conducting the method of this invention isv Material to be mixed is introduced through line shown. In this p r i l r f m, the m ials to controlled by valve 3! and is commingled with circulating materials passing through line 32. The mixture, is then passed through heat exchanger 33 wherein it will attain the proper temthe materials are withdrawn by means of line 13 and pump '14 and returned by means of line II perature and wherefrom it is withdrawn by 20 e e y caus g a continuous circulation of mameans of line 34 controlled by valve 35. The temperature of heat exchanger 33 is maintained by means of suitable convective fluid introduced through line 38 controlled by valve 31 which is terials from vessel 12 through pump 14 and bacl: to the vessel. At the same time, the materials to be mixed are passing through this circulatory system, the pressure therein is continually varied interconnected by means of lines 38 and 39 to a as by means of piston 16 Operating in cylinder 1! suitable source of air pressure. The convective fluid may be withdrawn from heat exchanger 38 by means of line 38 controlled by valve 31'. The air pressure to valve 31 is regulated by temperawhich is interconnected with vessel 12 by means of line 18. By varying the pressure on the system to a degree sufllcient to alternately cause vaporization and condensation as the materials are ture control instrument 40 which is interconso continually cllculaiiedively t e mixinsisobnected by means of a capillary tube or electrical conduits to temperature sensitive element 4| located in line 34. The material passing through valve enters a series of vertically disposed U- tained. Mixedmaterials may be withdrawn from :he system by means of line 19 controlled by valve Figure 6 is a modified form of the apparatus bends 42, valve 35 being controlled by means of 85 wn in Figure bin that a circulatory system is pressure controller 48 interconnected therewith by means of line 44. Air from a suitable source is introduced by means of line 45 to instrument 4! wherein this pressure is controlled and air at conset up within vessel H by means of an impeller 82. Materials to be mixed are introduced to vessel 8| by means 01 lines 83 and 84 controlled by valves 85 and 88 respectively and mixed materials trolled pressure is supplied to valve 35 by a s are withdrawn through line 81 controlled by valve of line 44. Instrument 43 is a pressure sensitive instrument available from any of a large number of instrument manufacturers and is connected by means of a suitable conduit 48 to the upper 88. Impeller 82 is rotated by motor 89 or other suitable conventional means. The pressure in vessel 8| is varied by means of piston 90 acting in cylinder tl which is connected to the vessel by extremity oi one of the vertically disposed umeans ofline 92.

bends. The pressure at this point will be maintained to effect vaporization of at least a portion of the fluids being mixed at the temperature of operation. The successive rise and fall of the The foregoing description and the accompanying drawings are intended as illustrative of a few of the many means by which this invention may be accomplished and should not be construed as mixing materials through U-bends 42 will cause 50 n ly limitingits broad s pe.

alternate vaporization and condensation due to. the difference in hydrostatic head thereby resulting in more intimate The mixed mate-- rials pass from the vertical U-bends through line I claim as my invention:

l. A method of mixing fluids which tend to segregate into separate phases when in contact with each other; said method comprising alter- 41 into pump I whereirom they are again circunately decreasing and increasing the pressure on lated through system. Mixed materials may be withdrawn from the system through line 40 controlled by valve 5}. T

Figure 4 illustrates another form of equipment suitable for the accomplishment of'the invention.

In this particular apparatus; materials to be mixed are introduced through line II controlled by valve 62 into reservoir 43. They are then withdrawn therefrom by means of line 84 and recirculated thereto by means of pump- 85 and 65 lines lit and 51. Upon leaving vessel I3, the materials to be mixed are successively passed through heat exchanger 58 and pressure regulating valve 58. In heat exchanger "the mixing materials will attain the desired temperature and the pressure of said materials will be controlled by valve 58 to obtain a pressure on the suction side of .pump 55 which is suiliciently low to vaporize a portion of the mixing materials. The temperae said fluids to cause alternate vaporization and condensation of at least'a portion thereof while maintaining the mixture in a state of turbulence sumcient to prevent substantial vapor. separation.

passing the mixture through a circulatory system I and maintaining it in a state of turbulence sufllclent to prevent vapor separation.

3. A'method of mixing fluids which tend to segregate into separate phases when in contact with each other, said method comprising" alternately decreasing and increasing the pressure on said fluids to cause their alternate partial vaporiture of exchanger u may be maintained at the u cation and c nd w ile m int ining the 2. A method of mixing fluids which tend to aseas'n mixture in a state of turbulence suflicient to prevent substantial vapor separation.

4. A method of mixing fluids which tend to segregate into separate phases when in contact with each other, said method comprising alternately decreasing and increasing the pressure on said fluids to cause their alternate partial vaporization and substantially complete condensation while maintaining the mixture in a state of turbulence s'umcient to prevent substantial vapor separation.

5. A method of emulsifying immiscible liquids which comprises alternately decreasing and increasing the pressure on said liquids to cause their alternate vaporization and condensation while maintaining the liquids in a state of turbulence suiiicient to prevent substantial vapor separation. x

6. A method of emulsifying immiscible liquids which comprises alternately decreasing and increasing the pressure on said liquids to cause their alternate partial vaporization and substantially complete condensation while maintaining the liquids in a state of turbulence sufilcient to prevent substantial vapor separation.

'7. A method of emulsifying immiscible liquids which comprises alternately decreasing and increasing the pressure on said liquids to cause their partial vaporization and substantially complete condensation while passing said liquids through a circulatory system and maintaining them in a state of turbulence suflicient to prevent vapor separation.

8. A method for intimately mixing fluids which tend to segregate into separate phases when in contact with each other, said method comprising commingling the fluids to be mixed, subjecting the resultant mixture to alternately decreased and increased pressures, a portion of said mixture being vaporized under the decreased pressure and the increased pressure being suiiicient to maintain the mixture substantially completely in liquid phase, and preventing separation of vapors from liquid by maintaining the mixture in a turbulent state during the subjection thereof to the aforesaid pressure conditions.

9. A method for intimately mixing immiscible liquids which comprises commingling the liquids to be mixed, subjecting the resultant mixture to alternately decreased and increased pressures, a portion of said mixture being vaporized under the decreased pressure and the increased pressure being sufllcient to maintain the mixture substantially completely in liquid phase, and preventing separation of vapors from liquid by maintaining the mixture in a turbulent state during the subjection thereof to the aforesaid pressure conditions.

CLARENCE a. cannon). 

